This invention relates generally to diffusion-absorption type refrigerating machines and more particularly to a diffusion-absorption type refrigerating machine in which refrigeration capacity loss due to auxiliary gas and refrigerant is small.
In known diffusion-absorption type refrigerating machines, the ammonia liquid which has condensed in the condenser flows into the evaporator in which it is evaporated as it mixes with hydrogen gas as an auxiliary gas. The mixture of the ammonia gas and hydrogen gas flows down through the evaporator into the liquid receiver and then flows upward through the absorber. As the mixture flows in the absorber, the ammonia gas is absorbed into a dilute ammonia solution flowing down the absorber and only the hydrogen gas rises back into the inlet of the evaporator. This rising hydrogen gas makes heat exchange in a heat exchanger with the mixture of the ammonia gas and the hydrogen which has been delivered from the evaporator, whereby the rising hydrogen gas is cooled by the mixture.
For the reasons to be set out hereinafter, it is desirable that the rising hydrogen be cooled as possible as it can in the heat exchanger. Moreover, it is also desirable that the ammonia liquid flowing from the condenser to the evaporator be cooled before it enters the evaporator.
However, in the known refrigerating machines of this type it has not been possible to fully cool the rising hydrogen and the ammonia liquid from the condenser, whereby a loss occurs in the refrigerating capacity of the refrigerating machines.